ContentCaptureSession | API reference

ContentCaptureSession | API reference | Android Developers

public abstract class ContentCaptureSession
extends Object implements AutoCloseable

Session used when notifying the Android system about events associated with views.

Summary

Public methods
`void`	`close()` Closes this resource, relinquishing any underlying resources.
`final ContentCaptureSession`	`createContentCaptureSession(ContentCaptureContext context)` Creates a new `ContentCaptureSession`.
`final void`	`destroy()` Destroys this session, flushing out all pending notifications to the service.
`void`	`flush()` Flushes an internal buffer of UI events and signals System Intelligence (SI) that a semantically meaningful state has been reached.
`final ContentCaptureContext`	`getContentCaptureContext()` Gets the `ContentCaptureContext` associated with the session.
`final ContentCaptureSessionId`	`getContentCaptureSessionId()` Gets the id used to identify this session.
`AutofillId`	`newAutofillId(AutofillId hostId, long virtualChildId)` Creates a new `AutofillId` for a virtual child, so it can be used to uniquely identify the children in the session.
`final ViewStructure`	`newViewStructure(View view)` Creates a `ViewStructure` for a "standard" view.
`final ViewStructure`	`newVirtualViewStructure(AutofillId parentId, long virtualId)` Creates a `ViewStructure` for a "virtual" view, so it can be passed to `notifyViewAppeared(ViewStructure)` by the view managing the virtual view hierarchy.
`final void`	`notifySessionPaused()` Notifies the Content Capture Service that a session has paused.
`final void`	`notifySessionResumed()` Notifies the Content Capture Service that a session has resumed.
`final void`	`notifyViewAppeared(ViewStructure node)` Notifies the Content Capture Service that a node has been added to the view structure.
`final void`	`notifyViewDisappeared(AutofillId id)` Notifies the Content Capture Service that a node has been removed from the view structure.
`final void`	`notifyViewInsetsChanged(Insets viewInsets)` Notifies the Intelligence Service that the insets of a view have changed.
`final void`	`notifyViewTextChanged(AutofillId id, CharSequence text)` Notifies the Intelligence Service that the value of a text node has been changed.
`final void`	`notifyViewsAppeared(List<ViewStructure> appearedNodes)` Notifies the Content Capture Service that a list of nodes has appeared in the view structure.
`final void`	`notifyViewsDisappeared(AutofillId hostId, long[] virtualIds)` Notifies the Content Capture Service that many nodes has been removed from a virtual view structure.
`final void`	`setContentCaptureContext(ContentCaptureContext context)` Sets the `ContentCaptureContext` associated with the session.
`String`	`toString()` Returns a string representation of the object.

Inherited methods

From class java.lang.Object

`Object`	`clone()` Creates and returns a copy of this object.
`boolean`	`equals(Object obj)` Indicates whether some other object is "equal to" this one.
`void`	`finalize()` Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.
`final Class<?>`	`getClass()` Returns the runtime class of this `Object`.
`int`	`hashCode()` Returns a hash code value for the object.
`final void`	`notify()` Wakes up a single thread that is waiting on this object's monitor.
`final void`	`notifyAll()` Wakes up all threads that are waiting on this object's monitor.
`String`	`toString()` Returns a string representation of the object.
`final void`	`wait(long timeoutMillis, int nanos)` Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis)` Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait()` Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

From interface java.lang.AutoCloseable


      close()

Closes this resource, relinquishing any underlying resources.

Public methods

close

public void close ()

Closes this resource, relinquishing any underlying resources. This method is invoked automatically on objects managed by the try-with-resources statement.

destroy

public final void destroy ()

Destroys this session, flushing out all pending notifications to the service.

Once destroyed, any new notification will be dropped.

flush

public void flush ()

Flushes an internal buffer of UI events and signals System Intelligence (SI) that a semantically meaningful state has been reached. SI uses this signal to potentially rebuild the view hierarchy and understand the current state of the UI.

UI events are often batched together for performance reasons. A semantic batch represents a series of events that, when applied sequentially, result in a meaningful and complete UI state.

It is crucial to call flush() after completing a semantic batch to ensure SI can accurately reconstruct the view hierarchy.

Premature Flushing: Calling flush() within a semantic batch may lead to SI failing to rebuild the view hierarchy correctly. This could manifest as incorrect ordering of sibling nodes.

Delayed Flushing: While not immediately flushing after a semantic batch is generally safe, it's recommended to do so as soon as possible. In the worst-case scenario where a flush() is never called, SI will attempt to process the events after a short delay based on view appearance and disappearance events.

newAutofillId

public AutofillId newAutofillId (AutofillId hostId, 
                long virtualChildId)

Creates a new AutofillId for a virtual child, so it can be used to uniquely identify the children in the session.

Parameters
`hostId`	`AutofillId`: id of the non-virtual view hosting the virtual view hierarchy (it can be obtained by calling `ViewStructure.getAutofillId()`). This value cannot be `null`.
`virtualChildId`	`long`: id of the virtual child, relative to the parent.

Returns
`AutofillId`	if for the virtual child. This value cannot be `null`.

Throws
`IllegalArgumentException`	if the `parentId` is a virtual child id.

notifySessionPaused

public final void notifySessionPaused ()

Notifies the Content Capture Service that a session has paused.

notifySessionResumed

public final void notifySessionResumed ()

Notifies the Content Capture Service that a session has resumed.

notifyViewAppeared

public final void notifyViewAppeared (ViewStructure node)

Notifies the Content Capture Service that a node has been added to the view structure.

Typically called "manually" by views that handle their own virtual view hierarchy, or automatically by the Android System for views that return true on View.onProvideContentCaptureStructure(ViewStructure,int).

Consider use notifyViewsAppeared(List) which has a better performance when notifying a list of nodes has appeared.

Parameters
`node`	`ViewStructure`: node that has been added. This value cannot be `null`.

notifyViewDisappeared

public final void notifyViewDisappeared (AutofillId id)

Notifies the Content Capture Service that a node has been removed from the view structure.

Typically called "manually" by views that handle their own virtual view hierarchy, or automatically by the Android System for standard views.

Consider use notifyViewsDisappeared(AutofillId, long) which has a better performance when notifying a list of nodes has disappeared.

Parameters
`id`	`AutofillId`: id of the node that has been removed. This value cannot be `null`.

notifyViewInsetsChanged

public final void notifyViewInsetsChanged (Insets viewInsets)

Notifies the Intelligence Service that the insets of a view have changed.

Parameters
`viewInsets`	`Insets`: This value cannot be `null`.

notifyViewTextChanged

public final void notifyViewTextChanged (AutofillId id, 
                CharSequence text)

Notifies the Intelligence Service that the value of a text node has been changed.

Parameters
`id`	`AutofillId`: of the node. This value cannot be `null`.
`text`	`CharSequence`: new text. This value may be `null`.

notifyViewsAppeared

public final void notifyViewsAppeared (List<ViewStructure> appearedNodes)

Notifies the Content Capture Service that a list of nodes has appeared in the view structure.

Typically called manually by views that handle their own virtual view hierarchy.

Parameters
`appearedNodes`	`List`: nodes that have appeared. Each element represents a view node that has been added to the view structure. The order of the elements is important, which should be preserved as the attached order of when the node is attached to the virtual view hierarchy. This value cannot be `null`.

notifyViewsDisappeared

public final void notifyViewsDisappeared (AutofillId hostId, 
                long[] virtualIds)

Notifies the Content Capture Service that many nodes has been removed from a virtual view structure.

Should only be called by views that handle their own virtual view hierarchy.

After UPSIDE_DOWN_CAKE, this method wraps the virtual children with a pair of view tree appearing and view tree appeared events.

Parameters
`hostId`	`AutofillId`: id of the non-virtual view hosting the virtual view hierarchy (it can be obtained by calling `ViewStructure.getAutofillId()`). This value cannot be `null`.
`virtualIds`	`long`: ids of the virtual children. This value cannot be `null`.

Throws
`IllegalArgumentException`	if the `hostId` is an autofill id for a virtual view.
`IllegalArgumentException`	if `virtualIds` is empty

setContentCaptureContext

public final void setContentCaptureContext (ContentCaptureContext context)

Sets the ContentCaptureContext associated with the session.

Typically used to change the context associated with the default session from an activity.

Parameters
`context`	`ContentCaptureContext`: This value may be `null`.

toString

public String toString ()

Returns a string representation of the object.

Returns
`String`	a string representation of the object.